Add release post scheduling to quick links

Why is this change being made?

I wanted to take a look of the upcoming TW lead for the release post and couldn't find that information easily.

Making the release post schedule page a quick link in the release post page makes it more apparent for someone that searches this information.

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
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  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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